Support MDX comments to disable link check

[BrunnerLivio]

At the moment MLC requires you to use a HTML comment to disable link checks. Unfortunately, in mdx v1 HTML comments are not valid.

In MDX it could look like this:

{/* markdown-link-check-disable-next-line */}
[Not a link](https://not-a-link.com)

[BrunnerLivio]

How about we make this configurable and leave it up to the user how the pattern for disabling comment checks should look like? Per default, it will off course use the standard <!--- -->, but add an option in the config.json with disablePattern